(a) Field of the Invention
The present invention relates to a user recognizing system and a method thereof. More particularly, the present invention relates to a user recognizing system and a method thereof capable of verifying the corresponding user based on a user image captured by an image camera.
(b) Description of the Related Art
Generally, a password, a key, a card, and the like have been used in order to verify a personal identity. However, a password is subject to be forgotten and a key or card is subject to be lost or stolen. Accordingly, a biometric recognizing method has been developed to verify a personal identity using biometric features belonging to respective persons.
However, such a biometric recognizing method is mainly designed to for security. Accordingly, it is required that user information will be obtained only under a strictly restricted environment or when a user positively cooperates in providing user information. However, when a system, such as a robot, authenticates a user identity it is difficult to strictly restrict the environment or to expect that the user will positively cooperate in providing user information.
For example, in the case that a robot system authenticates a representative biometric feature, that is, a face, based on the user recognizing method, the robot system can exactly authenticate a user's face only when the user views a camera at the front thereof under predetermined illumination conditions.
Therefore, such restrictions can be applied to a security system, but cannot be applied to general systems.
Recently, in order to solve the above problems, a method for modeling a face in a 3D image capable of authenticating a user identity regardless of intensity of illumination or a direction of the face has been developed. However, the method cannot yet solve the above problems when the user is viewed from behind or when the user is very far away from the robot system such that the face is too small for the robot system to authenticate.
Therefore, a method for reliably authenticating a user under more variable environments, which the system will confront with various users, is severely required in a system, such as a robot, requiring user recognizing.
The above information disclosed in this Background section is only for enhancement of understanding of the background of the invention and therefore it may contain information that does not form the prior art that is already known in this country to a person of ordinary skill in the art.